Autophagy promotes MHC class II presentation of peptides from intracellular source proteins

J Dengjel, O Schoor, R Fischer… - Proceedings of the …, 2005 - National Acad Sciences
J Dengjel, O Schoor, R Fischer, M Reich, M Kraus, M Müller, K Kreymborg, F Altenberend…
Proceedings of the National Academy of Sciences, 2005National Acad Sciences
MHC–peptide complexes mediate key functions in adaptive immunity. In a classical view,
MHC-I molecules present peptides from intracellular source proteins, whereas MHC-II
molecules present antigenic peptides from exogenous and membrane proteins.
Nevertheless, substantial crosstalk between these two pathways has been observed. We
investigated the influence of autophagy on the MHC-II ligandome and demonstrated that
peptide presentation is altered considerably upon induction of autophagy. The presentation …
MHC–peptide complexes mediate key functions in adaptive immunity. In a classical view, MHC-I molecules present peptides from intracellular source proteins, whereas MHC-II molecules present antigenic peptides from exogenous and membrane proteins. Nevertheless, substantial crosstalk between these two pathways has been observed. We investigated the influence of autophagy on the MHC-II ligandome and demonstrated that peptide presentation is altered considerably upon induction of autophagy. The presentation of peptides from intracellular and lysosomal source proteins was strongly increased on MHC-II in contrast with peptides from membrane and secreted proteins. In addition, autophagy influenced the MHC-II antigen-processing machinery. Our study illustrates a profound influence of autophagy on the class II peptide repertoire and suggests that this finding has implications for the regulation of CD4+ T cell-mediated processes.
National Acad Sciences